lange



March: 3, 1964 P. H. LANGE, JR., ETAL GALLERY BULLET Filed Jan. 3, 1962INVENT PAUL H. LANGE, J/P.

ORS.

OMER N. DEJAR/VETT ATTORNEY United States Patent Ofilice 3,123,003GALLERY BULLET Paul H. Lange, In, New Haven, Conn, and Omer W. DeJarnett, Alton, 111., assignors to Ulin Mathieson Chemical Corporation,a corporation of Virginia Filed Jan. 3, 1962, Ser. No. 164,157 9 Claims.(Cl. 10 2-31) This invention relates to novel formulations for use inthe manufacture of bullets, and more particularly it is concerned withformulations which can be used in the preparation of a uniquedisintegrating gallery bullet.

In the production of bullets for use in shooting galleries, a primaryconsideration should be to prepare a bullet which disintegrates on thetarget without excessive splashback of bullet particles. Conventionallead bullets, While possessed of good ballistic properties, are not safeto use in such galleries because of the splashback of large leadparticles from the target. Various other types of bullets have beendesigned in an effort to overcome these difiiculties.

For example, US. Patents 2,105,528, 2,168,381 and 2,315,853 disclose thepreparation of bullets which have been formulated by mixing lead withother metals such as zinc or copper or another compound such as ironoxide. These bullets, While much superior to plain lead bullets for usein shooting galleries, still do not disintegrate satisfactorily upon thetarget and a great deal of litigation has resulted from injuries causedby splashback of particles.

have been molded into a homogeneous body with the aid of a thermoplasticbinder. These bullets are characterized by improved safety featuressince the tendency for large particles to spatter about upondisintegration has been reduced. However, since these bullets are muchlighter than lead bullets, they must be fired at a much greater velocityin order level of the lead bullets. As a loud noise level is and this isan especially undesirable characteristic in enclosed shooting galleries.

Therefore the primary object of this invention is to prepare novelformulations which can be used in the production of a unique gallerybullet. A more specific being subject to the dangerous spattering oflead particles inherent in many of the prior art gallery bullets.

Still another object of this invention is to prepare an improved gallerybullet which will not be characterized by an undesirably high noiselevel when fired. Other objects will be noted in or will be obvious fromthe following discussion.

These objects have been accomplished in accordance with the presentinvention. Novel formulations have been prepared which can be used tomake gallery bullets possessing new and improved qualities. From theseforthe strength to withstand shooting, have a relatively high densityand furnish important safety features to the user. The resultant gallerybullets are also characterized by excellent disintegration properties,and there is no objectionable noise level when the bullets are fired.

der metallurgy techniques.

3,123,903 Patented Mar. 3, 1964 FIGURE 1 is a side view of a bulletprepared from the formulations described herein.

FIGURE 2 is a sectional View of the bullet shown in FIGURE 1.

It has been found that for best results, a relatively coarse lead powdershould be utilized in these novel formulations. It is preferred to uselead powder of such a size that a 2% maximum of such powder would Thereare several reasons for the preferential use of the aforementionedparticle size. The use of such coarse particles is necessary to providegood feeding in tabletting presses. In addition, finer powders havingmuch greater surface area are more affected by corrosion products ontheir surfaces. On the other hand if too coarse particles are used, thehighly undesirable splashback problems may be again encountered.

It is known that to surface corrosion,

full strength upon compaction by pow- The corroded particles will notadhere satisfactorily to each other because the corrosion products arerefractory in nature. Therefore in order to prepare bullets of adequatestrength, it is nections containing equal amounts by weight of lead andiron powders. However, in general, the preferred formulations includethe following proportions of ingredients: iron-30 to 17 parts by weight,lead70 to 83 parts by weight and thermosetting resin-0.1 to 1.0 part byWeight.

The iron powder which can be used in these novel formulations isproduced by the reduction process. For best results, the iron powdershould be so sized that 98% will pass through an mesh screen and 2535%will pass through a 325 mesh screen.

Superior adhesion to the surfaces of the metal powders involved in theformulations is an important requisite of the thermosetting resins whichcan be used in the practice of this invention. It has been found thatthe use of For example, bisphenol A may be replaced by other diphenols,glycols or even glycerinc. Before curing, the desirable epoxy resinssuitable for use in these formulations are viscous liquids or clearbrittle solids having molecular weights from about 600 to 8000. 7

It has also been found that various polyesters and polyurethanes can beused as the required resins. Gallery bullets possessing the desiredcharacteristics have been prepared when these compounds have beenutilized instead of epoxy resins in the metal powder formulations.

It is necessary that the resin in the final powder mix be in a solidnon-tacky form before this mix is introduced into the tabletting machineor caking and sticking of the powder mix will occur during thisoperation. Liquid resins can however be satisfactorily utilized if theyare partially polymerized to a solid non-tacky state before thisoperation.

Usually the curing of such thermosetting resins is achieved by using acatalyst or hardener but satisfactory results have been obtained in theabsence of these compounds. The preferred proportion of thermosettingresin is 0.75 part per 100 parts of metal powders. It has been foundthat a proportion as small as 0.10 part will yield bullets; theperformance of these bullets however, is inferior to those of thepreferred composition. It has also been found that a proportion as highas 1.0 part will yield bullets, but these bullets do not possess thedesirable ballistic characteristics exhibited by those containing thepreferred proportion.

In powder metallurgy, it is conventional to use a lubricant such as ametallic stearate to cause the powdered metal to flow and compactsatisfactorily. However it has been found that with the use ofoil-treated lead powder, no other lubricant is required to obtainsatisfactory flow of the powdered metals. If desired a metallic stearatesuch as lithium stearate may be used as a lubricant in the proportion of0.01 to 0.5 part per 100 parts of powdered metal.

Some typical preparations of gallery bullets involving the use of thesenovel formulations are herein described.

Example 1 Formulation: Percent by wt., parts Lead powder, Type 40 B,oil-treated, Glidden Co 83 Iron powder, Ancor 80 1 17 Epon 1004 0.75

Obtained from Hoeganes Sponge Iron Corporation,

"Epon is a trademark for condensation products of epichlorohydrin andbisphenol-A. Obtained from Shell Chemical Corporation.

The iron powder and solid epoxy resin were blended in a double arm typeblender for 15 minutes above the melting point of the resin (95100 C.).The resulting mix was cooled and crushed in the same blender and thenground to pass through a 30 mesh screen.

Then the oil-treated lead was added to the iron-resin mix, and theentire mixture was blended and ground to pass through a 30 mesh screen.The powder mix was then compacted into bullets in a rotary tablettingpress. The bullets were cured for 3 hours at 300 F., tumbled to removeflash and then loaded in the usual manner.

Example 2 Formulation: Percent by wt., parts Lead powder, Type 40 B,oil-treated, Glidden Co 83 Iron powder, .Ancor 80 17 Epon 828, ShellChemical Corporation 0.75

The liquid epoxy resin was mixed with metaphenylenediamine (13% by wt.of resin) and the mixture was warmed and stirred above the melting pointof the diamine (ca. 63 C.).

This mixture, while in a liquid form, was stirred with the iron powderand left at room temperature for a period of about twenty-four hours atwhich point the solid mixture was no longer tacky. The mix was thenground to pass through a 30' mesh screen.

Then the oil-treated lead was added to the iron-resin mix, and theentire mixture was blended and ground to pass through a 30 mesh screen.Bullets were prepared from this mixture in the same manner as in Example1.

Example 3 Formulation: Percent by wt., parts Lead powder, Type 40 B,oil-treated, Glidden Iron powder, Ancor 17 Estane 5740242 1 0.75

lhis is a polyurethane obtained from the B. F. Goodrich ChemicalCompany. It is made with diphenylmethane-p,pdiisocyanate, adipic acidand butanediol-lA.

The Estane was dissolved in 10 cc. of methyl ethyl ketone by refluxingon a steam bath. Then 0.024 part of dicumyl peroxide and the iron powderwere added to the solution, and the ketone was driven off on a steambath. The resulting m'nr was ground to pas through a 30 mesh screen.

Then the oil-treated lead was added to the iron-resin mix, and theentire mixture was blended and ground to pass through a 30 mesh screen.Bullets were prepared from the mixture in the same manner as in Example1.

Example 4 Formulation: Percent by wt., parts Lead powder, Type 40 B,oil-treated, Glidden Co. 83 Iron powder, Ancor 8O 17 Atlac 382 1 styrenemonomer 0.75

Atlae is a trademark for polyester resins prepared by reaction of abisphenol with unsaturated compounds such as funiaric .or maleicanhydride. Product obtained from Atlas Powder Company.

Equal amounts (0.375 part by weight) of Atlac 382 and styrene monomerwere stirred together until a clear solution was obtained, and then 2%of benzoyl peroxide (based on total weight of resin and styrene) wasadded and stirred. The iron powder was added and blended, and theresulting mix was allowed to stand at F. for two hours. At the end ofthis period, the solid mix was non-tacky, and it was ground to passthrough a 30 mesh screen.

Then the oil-treated lead was added to the iron-resin mix and the entiremixture was blended and ground to pass through a 30 mesh screen. Bulletswere prepared from this mixture in the same manner as in Example 1.

A polyester resin prepared by reaction of a diol and a dibasic acid andcontaining styrene monomer. Obtained from Allied Chemical Corporation.

To the Plaskon 941 was added 2% by weight of benzoyl peroxide withstirring. The iron powder was then added with stirring; and the mixturewas allowed to stand at 160 F. for two hours. At the end of this period,the solid mix was non tacky, and it was ground to pass through a 30 meshscreen.

Then the oil-treated lead was added to the iron-resin mix and the entiremix was blended and ground to pass through a 30 mesh screen. Bulletswere prepared from this mixture in the same manner as in Example 1.

The bullets prepared in these experiments possess the good ballisticcharacteristics of lead bullets and are safe to use in shootinggalleries since the dangerous back spattering of particles has beeneliminated. Furthermore the use of these bullets is not accompanied byan objectionable noise level.

What is claimed is:

1. A formulation suitable for preparing a disintegrating gallery bulletby powder metallurgy techniques comprising a mixture of 7083 parts byweight of lead powder the surface of which is substantially free ofcorrosion and oxidation products, 30-17 parts by weight of iron powderand 0.1-1.0 part by weight of a thermosetting resin.

2. The formulation of claim epoxy resin having 8,000.

3. The formulation of claim 1 wherein said resin is selected from thegroup consisting of a polyester resin and a polyurethane resin.

4. A formulation suitable for preparing a disintegrating gallery bulletby powder metallurgy techniques comprising a mixture of (a) 70-83 partsby weight of oil-treated lead powder,

said lead powder particles being so sized that a 2% maximum of saidpowder would be retained on a 40 mesh screen and a 65% minimum of saidpowder would be retained on a 100 mesh screen, and

(b) 30-17 parts by weight of iron powder, said iron powder particlesbeing so sized that 98% of said powder would pass through an 80 meshscreen and 25-35% of said powder would pass through a 325 mesh screen,and

(c) 0.1-1.0 part by weight of a thermosetting resin.

5. The formulation of claim 4 wherein said resin is an epoxy resinhaving a molecular weight from about 600 to 8,000.

6; The formulation of claim 4 wherein said resin is selected from thegroup consisting of a polyester resin and a polyurethane resin.

1 wherein said resin is an a molecular weight from about 600 to 7. Aformulation suitable for preparing -a disintegrating gallery bullet bypowder metallurgy techniques comprising a mixture of 83 parts by weightof lead powder the surface of which is substantially free of corrosionand oxidation products, 17 parts by weight of iron powder and 0.75 partby weight of an epoxy resin having a molecular weight of from about 600to 8,000.

8. A disintegrating gallery bullet comprising a compacted mixture of70-83 parts by weight of lead powder the surface of which issubstantially free of corrosion and oxidation products, -17 parts byweight of iron powder, and 0.1 to 1.0 part by weight of a thermosettingresin selected from the group consisting of an epoxy resin having amolecular weight of from about 600 to 8,000, a polyester resin and apolyurethane resin.

9. A disintegrating gallery bullet comprising a compacted mixture of 83parts by weight of oil-treated lead powder, 17 parts by weight of ironpowder and 0.75 part by weight of an expoxy resin having a molecularweight of from about 600 to 8,000.

References Cited in the file of this patent UNITED STATES PATENTS

1. A FORMULATION SUITABLE FOR PREPARING A DISINTEGRATING GALLERY BULLETBY POWDER METALLURGY TECHNIQUES COMPRISING A MIXTURE OF 70-83 PARTS BYWEIGHT OF LEAD POWDER THE SURFACE OF WHICH IS SUBSTANTIALLY FREE OFCORROSION AND OXIDATION PRODUCTS, 30-17 PARTS BY WEIGHT OF IRON POWDERAND 0.1-1.0 PART BY WEIGHT OF A THERMOSETTING RESIN.